1. Field of the Invention
This invention relates to the removal of masking formyl groups from amino acid and peptide esters having free carboxyl groups.
2. Description of the Prior Art
While the amino groups of amino acid and peptide esters having free carboxyl groups are readily masked by formyl groups, it was common practice heretofore instead to employ benzyloxycarbonyl and tert-butyloxycarbonyl groups for this purpose in the synthesis of peptides and similar reactions. These known masking groups require phosgene, a dangerously toxic gas, for their introduction, but they have the advantage of being removed easily when no longer required. No practical method of removing formyl groups from the nitrogen atoms of amino acid esters or peptide esters having free carboxyl groups was available prior to this invention.